• James Hogan's avatar
    MIPS: KVM: Restore host EBase from ebase variable · 878edf01
    James Hogan authored
    The host kernel's exception vector base address is currently saved in
    the VCPU structure at creation time, and restored on a guest exit.
    However it doesn't change and can already be easily accessed from the
    'ebase' variable (arch/mips/kernel/traps.c), so drop the host_ebase
    member of kvm_vcpu_arch, export the 'ebase' variable to modules and load
    from there instead.
    
    This does result in a single extra instruction (lui) on the guest exit
    path, but simplifies the code a bit and removes the redundant storage of
    the host exception base address.
    
    Credit for the idea goes to Cavium's VZ KVM implementation.
    Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
    Cc: Paolo Bonzini <pbonzini@redhat.com>
    Cc: Radim Krčmář <rkrcmar@redhat.com>
    Cc: Ralf Baechle <ralf@linux-mips.org>
    Cc: linux-mips@linux-mips.org
    Cc: kvm@vger.kernel.org
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    878edf01
mips.c 40.3 KB